1. Field of the Invention
The present invention relates to an information communication device for transmitting and receiving information by means of radio.
2. Related Arts
A polarization diversity communication system for exchanging information using radio signals that are vertically and horizontally polarized is available. In carrying out polarization diversity communication, two antennas for transmitting and receiving radio signals with vertical and horizontal polarization respectively are used. For example, an antenna formed within a printed wiring board in an electronic device and an antenna vertically erected on the printed wiring board are used. As the dispositions of the respective antennas are subjected to restriction due to the structure of a device enclosure, an inverted-F antenna is often employed for the antenna vertically erected on the printed wiring board to suppress the height.
A typical inverted-F antenna shows a directivity pattern of a component perpendicular to the board surface, which is similar to that of a dipole antenna, as shown in FIG. 8. That is, there exists a null point depending on direction. Therefore, it may not be possible to ensure that a signal having sufficient strength is directed to a certain communication destination in a particular direction, depending on the manner in which the enclosure of the product is disposed.